Important: you should take care of your assets and of the routing. If there is some errors, they should be written in your app/log/dev.log file, or at last in your apache error.log.

Finally, create the view that will be included:

{# ajaxTest.html.twig #}
This is <em>some</em> remote content

This sample gave me the following result:

Note: there is still some assetic errors (see the close button at the right of the image), because I installed facebox quickly. The point of your question was the access to remote content, and here you have a sample you can follow to find your mistake.

hm.. thx i am not sure where my mistake is because my facebox for images is working... But i solved it another way... i trigger function on specific elements when click. Then the function get content from the url and finally it move it to the facebox box and open it.
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TrkiMay 14 '13 at 7:07

yeah, looks tricky... good if you found a solution anyway.
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Alain TiembloMay 14 '13 at 7:38